\[5 - \frac{3}{4}x^{3};\ \ x = - 2:\]
\[5 - \frac{3}{4} \cdot ( - 2)^{3} = 5 - \frac{3}{4} \cdot ( - 8) =\]
\[= 5 + 3 \cdot 2 = 11.\]